Electronics Forum | Fri May 02 09:49:19 EDT 2003 | tommyg_fla
3NaH2PO3 + H2SO4 + 2H2 + Ni^0 Potassium is co-deposited with the nickel, as follows: H2PO2^- + Hads => H2O + OH^- + P 3H2PO2^- + P => H2PO3^- + H2O + 2OH^- What is Hads?
Electronics Forum | Tue May 06 12:01:47 EDT 2003 | davef
H2PO3^- + H2O + 2OH^-" is not balanced. It should be "3H2PO2^- => H2PO3^- + H2O + 2OH^- + 2P" tommyg_fla I'll respond your question, but I've got alligators up to here, and they're doing what alligators do.
Electronics Forum | Mon May 05 11:35:00 EDT 2003 | Grant
Hi, This is an interesting point. I use Koki paste from Japan, and it's wonderful, however what properties of solder paste would make it "anti tombstone" paste? How does led free effect tomb-stoning? That would be interesting to know. We might go
Electronics Forum | Mon May 05 18:48:23 EDT 2003 | Kris
Hi, It is expected that lead-free will have reduced tomstoning. As it has a higher surface tension and does not wet as well as the tinlead paste it exibit lower tombstoning. Addiotnaly commercialy available lead-free alloys may not be true eutectic
Electronics Forum | Wed May 07 09:02:17 EDT 2003 | Kris
Hi SnAg is a binary alloy and does not have the same effect as a ternary SnAgCu alloy as far the pasty range is concerned. But then paste only can do so much. The best way to do it is to have proper pad design, controlled placement and reflow. I w
Electronics Forum | Mon May 26 04:02:13 EDT 2003 | Franky
Dear sir, I think so with every idea , everyone is correct , paste , pattern of pad design ,profiling or solder mask on PCB ,and one of the cause of tombstone that I found is alignment of machine placing and solder printing , from my experience many
Electronics Forum | Fri May 30 18:30:32 EDT 2003 | russ
Okay, Okay, I will convert to the metric system. I would still rather say 1 mm instead of 10 microns. As far as paste how about "really little" and "really really little" (type 3 and 4 respectively) This term (micron)is good for people unlike me t
Electronics Forum | Tue Jun 03 21:50:57 EDT 2003 | yukim
A question regarding the rampup slop: as we cannot make the preheat time long enough due to our reflow oven limits, a Loctite technician suggested we increase the rampup slope, between the initial point (25C) and 80C, to 4C/sec, as between these temp
Electronics Forum | Thu Aug 28 20:24:30 EDT 2003 | yukim
Hi, do you know how much the problem can be reduced by using anti-tombstoning solder paste? I tried two different lots using same solder paste (containing Ag). With one we did not see any improvement and with the other one, a lot. So, I am not quite
Electronics Forum | Fri Jul 30 00:21:01 EDT 2004 | Jet
Hi, Very interesting article on tombstone issue, i'm facing tombstone issue for 0805 IDC component, i've redesign the stencil aperture and change to lead free paste, the tombstone is reducing but not fully eliminated, however there is a problem i fa
